1. Field
The present disclosure relates generally to regulator circuitry, and more particularly, to a feed-forward frequency control method for a current mode hysteretic buck regulator.
2. Background
Hysteretic voltage regulators, e.g., buck regulators, are used in applications which require good transient response and/or fast speed of operation. This control scheme has variable switching frequency which helps achieve fast load transient response. However, average frequency control is useful for bucks which operate in an EMI sensitive environment like mobile phone applications. Phase locked loops can be used to control switching frequency but such implementation is costly in terms of power, area and typically requires external components like off-chip capacitors. In addition, closed loop average frequency control methods interfere with the dynamics of the main voltage control loop.